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  • Early(ish) game checker play

    From Timothy Chow@21:1/5 to All on Mon Oct 24 08:20:25 2022
    XGID=--a-BBC-----dE-a-c-d--b-BA:0:0:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O O X |
    | X O | | O O X |
    | X O | | O |
    | X | | O |
    | X | X | |
    | |BAR| |
    | | | |
    | O | | |
    | O | | X |
    | O | | X X X |
    | O | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 174 O: 139 X-O: 0-0
    Cube: 1
    X to play 41

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Mon Oct 24 14:14:17 2022
    On 10/24/2022 8:20 AM, Timothy Chow wrote:
    XGID=--a-BBC-----dE-a-c-d--b-BA:0:0:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
     +13-14-15-16-17-18------19-20-21-22-23-24-+
     | X     O     O    |   | O        O     X |
     | X           O    |   | O        O     X |
     | X           O    |   | O                |
     | X                |   | O                |
     | X                | X |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     | O                |   |                  |
     | O                |   | X                |
     | O                |   | X  X  X          |
     | O                |   | X  X  X     O    |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 174  O: 139 X-O: 0-0
    Cube: 1
    X to play 41

    X can play bar/24 13/9 and bring a ninth checker into the zone in a
    blitz-ish position, but I don't like the looks of three checkers on the
    ace point this early in the game. O has ten in the zone so leaving three
    blots in her home board seems too risky. That leaves 21/20 or 6/5 as the
    ace if I enter with the four. Not sure which is better, but I'll go for
    bar/20.

    --
    Ah....Clem
    The future is fun, the future is fair.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Wed Oct 26 08:33:05 2022
    XGID=--a-BBC-----dE-a-c-d--b-BA:0:0:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O O X |
    | X O | | O O X |
    | X O | | O |
    | X | | O |
    | X | X | |
    | |BAR| |
    | | | |
    | O | | |
    | O | | X |
    | O | | X X X |
    | O | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 174 O: 139 X-O: 0-0
    Cube: 1
    X to play 41

    XG strongly prefers to stack a third checker on the 24pt and hit loose
    with only 7 checkers in the zone. This still looks unnatural to me, but
    I interpret the play as a tempo hit. Given free rein, many of O's rolls
    play well, letting her make a good point or run her last checker.

    For comparison, see the variant.

    1. Rollout¹ Bar/24 6/2* eq:-0.323
    Player: 44.11% (G:12.19% B:0.42%)
    Opponent: 55.89% (G:21.79% B:2.34%)
    Confidence: ±0.016 (-0.339..-0.306) - [100.0%]

    2. Rollout¹ Bar/20 eq:-0.405 (-0.082)
    Player: 41.53% (G:10.82% B:0.41%)
    Opponent: 58.47% (G:19.71% B:1.63%)
    Confidence: ±0.014 (-0.419..-0.390) - [0.0%]

    3. Rollout¹ Bar/21 24/23 eq:-0.409 (-0.087)
    Player: 41.21% (G:10.66% B:0.39%)
    Opponent: 58.79% (G:20.63% B:1.28%)
    Confidence: ±0.014 (-0.423..-0.396) - [0.0%]

    4. Rollout¹ Bar/21 6/5 eq:-0.432 (-0.109)
    Player: 40.55% (G:10.45% B:0.37%)
    Opponent: 59.45% (G:19.77% B:1.56%)
    Confidence: ±0.016 (-0.448..-0.416) - [0.0%]

    5. Rollout¹ Bar/24 13/9 eq:-0.461 (-0.139)
    Player: 40.24% (G:11.06% B:0.40%)
    Opponent: 59.76% (G:21.16% B:2.19%)
    Confidence: ±0.018 (-0.480..-0.443) - [0.0%]

    ¹ 1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    eXtreme Gammon Version: 2.19.211.pre-release

    -------
    Variant
    -------

    XGID=-a--BBC-----dE-a-c-d--b-BA:0:0:1:51:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O O X |
    | X O | | O O X |
    | X O | | O |
    | X | | O |
    | X | X | |
    | |BAR| |
    | | | |
    | O | | |
    | O | | X |
    | O | | X X X |
    | O | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 174 O: 140 X-O: 0-0
    Cube: 1
    X to play 51

    1. XG Roller++ Bar/20 24/23 eq:-0.349
    Player: 42.84% (G:10.83% B:0.38%)
    Opponent: 57.16% (G:19.84% B:0.96%)

    2. XG Roller++ Bar/20 6/5 eq:-0.356 (-0.007)
    Player: 42.55% (G:10.41% B:0.32%)
    Opponent: 57.45% (G:18.31% B:1.41%)

    3. XG Roller++ Bar/24 13/8 eq:-0.404 (-0.055)
    Player: 41.96% (G:10.39% B:0.35%)
    Opponent: 58.04% (G:20.49% B:1.94%)

    4. XG Roller++ Bar/24 6/1* eq:-0.442 (-0.093)
    Player: 41.02% (G:11.21% B:0.31%)
    Opponent: 58.98% (G:21.03% B:2.03%)

    eXtreme Gammon Version: 2.19.211.pre-release

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)